Chair base



FIG. 1 is a perspective view of a chair base in accordance with a first embodiment of the present invention;

FIG. 2 is a front view of the chair base of FIG. 1;

FIG. 3 is a rear view of the chair base of FIGS. 1 and 2;

FIG. 4 is a top view of the chair base of FIGS. 1-3;

FIG. 5 is a bottom view of the chair base of FIGS. 1-4;

FIG. 6 is a side view of the chair base of FIGS. 1-5, the opposite side being a mirror image thereof;

FIG. 7 is a perspective view of a chair base in accordance with a second embodiment of the present invention;

FIG. 8 is a front view of the chair base of FIG. 7;

FIG. 9 is a rear view of the chair base of FIGS. 7 and 8;

FIG. 10 is a top view of the chair base of FIGS. 7-9;

FIG. 11 is a bottom view of the chair base of FIGS. 7-10; and,

FIG. 12 is a side view of the chair base of FIGS. 7-11.

The broken lines shown in the Figures are for environmental purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a chair base, as shown and described. 